191t0) TWISS—PROTHALLIA OF ANEIMIA AND LYGODIUM 171 
Fungi were kept down by the potassium permanganate solution 
advised by LANG (15). Ina letter from Dr. LANG to Dr. CoULTER 
the directions called for a solution decidedly pink; I used with success 
0.015" potassium permanganate in 3.5 liters of water. 
Drawings of the early stages were made from living material. 
The older prothallia were killed with Flemming’s weaker solution (8), 
imbedded in paraffin, and the sections stained with safranin and 
iron alum-hematoxylin. 
Lygodium 
The species studied was Lygodium circinatum (Burm.) Sw. (L. 
dichotomum Sw.), spores of which were obtained through the kindness 
of Dr. J. N. Roser, from the botanical gardens at Washington, D. C. 
SPORE COATS 
The coats reported for the spores of Filicineae are an outer exceed- 
ingly delicate epispore, a heavier exine having usually peculiar mark- 
ings, and a thinner intine which covers the emerging papilla when 
germination occurs. Paraffin sections of spores of Lygodium, how- 
ever, showed the possibility of a different situation, and accordingly 
a study of the development of the coats was undertaken. For this 
Study I was most fortunate in having access to slides prepared by 
BrnForp (5) in his work on the sporangia of Lygodium circinatum, 
and thanks are due him for the aid afforded’ by his preparations. 
The slides were stained with safranin and gentian violet, and this 
Should be kept in mind when reading the account of the coloring of 
the different coats. The sporangia are produced in acropetal suc- 
cession, so that it is easy to get a clear picture of the different stages. 
When the spore mother cell rounds off, the wall is exceedingly 
delicate, and at the tetrad stage no remnant of it could be identified 
with any certainty. As fig. 1 shows, there is a clear space about the 
tetrad, so that the tapetal protoplasm with its large nuclei does not 
touch the spores. The protoplasm at the edge of this clear space was 
carefully examined for traces of the old mother cell wall, but none 
could be found. Moreover, the same clear space was seen about 
the spore mother cells themselves in some of the sporangia. Whether 
the clear space was due to plasmolysis caused by the fixing agent 
